Newsgroups: comp.parallel.pvm From: Pascal Bauler Reply-To: pascal.bauler@ci.educ.lu Subject: Re: passing message between two unrelated processes Organization: ULg Date: Sat, 25 Oct 1997 22:59:15 -0400 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <3452B203.5BCF@ci.educ.lu> Julian Zhao wrote: > > Hi, > > I am MPI user and new in PVM. Now I start two processes by pvm, say A > and B, separately. In order to pass a message from process A to process > B, A need to know B's process id (tid). My question is how A gets this > information to call pvm_send( int tid, int message)? > > Thank you! > > Julian > > -- > Julian Zhao, PhD > Microcosm Technologies, Inc. > 101 Rogers St., Suite 213 > Cambridge, MA 02142 > Fax: (617)621-7838 > Email julian@memcad.com When you want to make interact two indendent tasks there are 2 conditions which must be verified 1. the two tasks must run on the same virtual machine (if the two tasks are launched by the same user, this condition is verified) 2. you must know the two tids... in order to do so, each application may create a group (pvm_joingroup). PVM attributes an instance number to each task inside the group. This instance number is unique inside 1 group and attributed sequentially starting with 0. Now you may get the tids with the instruction pvm_gettid(). Example task A pvm_joingroup("taskA") tidB=pvm_gettid("taskB",0) task B pvm_joingroup("taskB") tidA=pvm_gettid("taskA",0) /* now the two tasks may communicate */ Best regards Pascal -- --------------------------------------------------- Pascal Bauler Algorithmique et Ingenierie du Logiciel Universite de Liege Tel: (0032/4) 366 2609 ---------------------------------------------------